The ruling on the prayer of one who prays alone behind the rows

Question:
He says: Honorable Shaykh, may Allah grant you success, what is the stronger position, supported by evidence, regarding a person praying alone behind the row? And if he prays alone, is his prayer valid?

Answer:
The stronger position in the evidence is that the prayer is not valid, because the Prophet (peace and blessings be upon him) saw a man praying behind the row and ordered him to repeat the prayer, and the Prophet (peace and blessings be upon him) said: Does the prayer of a single person not invalidate the prayer? Yes.